You may have already seen AED's whenever you've visited a public building or office. These devices are now commonly available, sparking your curiosity about why they're so prevalent. So – just what is an AED?

An AED, or automated external defibrillator, is a sophisticated, yet easy-to-use medical device which analyzes the heart's rhythm, for those people experiencing sudden cardiac arrest. If necessary, it delivers an electrical shock, or "defibrillation" to help the heart re-establish an effective rhythm.

Automatic external defibrillators, or AEDs, are small computerized devices that analyze heart rhythms and provide the shock needed for defibrillation. Through electrodes placed on a patient’s chest, a processor inside the AED analyzes the victim’s heart. The machine will not shock unless it is necessary; AEDs are designed to shock only when Ventricular Fibrillation (VF), a common cause of cardiac arrest, is detected.

After the processor analyzes the heart rhythm and determines a shock is required, an electric current is delivered to the heart through the victim’s chest wall through the adhesive electrode pads. The shock delivered by a cardiac defibrillator interrupts the chaotic rhythm and allows it to return to normal.

AED's are designed to be used by anyone, and usually provide simple visual or audio commands. Most automatic external defibrillators (AEDs) are designed to be used by non-medical personnel, such as fire department personnel, police officers, lifeguards, flight attendants, security guards, teachers, and even family members of high-risk persons. Having an AED readily available can save the life of someone who is in cardiac arrest, which is why we see them more and more often in public places. Anyone can buy an AED for use at home, work, school or anywhere there might be a need for defibrillation.

For some people who have a high risk of cardiac arrest, having an AED can provide peace of mind and might help save their lives. In addition, every state has enacted laws and/or regulations requiring that public gathering places have AEDs available. The intent of these laws and regulations are so sudden cardiac death or neurological damage will not be the end result in any of these attacks.